Bone saw



Dec. 7, 1948. I G. v. CARROLL BONE SAW 2 Sheets-Shet 1 Filed Nov. 1, 1946 Dec; 7, 1948. a. v. CARROLL BONE SAW 2 Sheets-Sheet 2 Filed Nov. 1, 1946 m H m RN .WA n 1 v E Y. w mm M, m

, MF/Al) m v J [555: X an mm an N Patented Dec. 1948 som saw. Gay V. Carroll, liouston, "lex Application November 1, 1946, rs erial No. 707,277

1 invention relates toafsurgical instrument, and more particularly too. bone saw. T

The primary object of the inventionisto facilitate the periorming oila.surgical operationin which itis desiredto severabone.

Another object is t enable a surgeon form an incision in a bone to thedesired depth, or to completely sever the bone according to therequirements of thecase.

Still another object of the .inventionis 1 to,

sci-aims. (cums-1317) steady the object to be operated upon during the sawing operation. T The above and otherobjects may be attained .by employingthis invention which embodies among its features a saw guard having spaced arms adapted partially to embrace and st'eady an; objecttto be operated upon, a power driven saw mounted to move transversely of the saw guard in a plane perpendicular to the axis of an object embraced and steadied by the arms, and

means to move the sawtoward an embraced object along an axis which lies parallel with the longitudinal axesof the arms. l 1

Other. features include means yieldingly to retract the saw from the embraced object, a crank for moving the. saw and a flexible cable establishing driving connection betweenj the "crank discand a' prime mover by which power may be transmitted for theoperation of the saw.

In the drawings, 8 u u Figure 2 is a longitudinal sectional view through the saw illustrated in Figure 1,

Figure 3 is a transverse sectional view taken substantially along the line 3--3 of Figure 2,

Figure 4 is a transverse sectional view taken substantially along the line 4-4 of Figure 2,

Figure 5 is a transverse sectional view taken substantially along the line 5-5 of Figure 1,

Figure 6 is a fragmentary plan view taken substantially along the line 66 of Figure 1, and

Figure 7 is a side view of a modified form of saw guard.

Referring to the drawings in detail a frame designated generally I is provided and comprises a tubular shell ll provided at one end with screw threads to which a handle designated generally I2 is. adapted to be attached. The tubular body II is provided with a filler member l3 (Fig. 4) which is provided with a longitudinally extending slot 14 in which the saw blade to be more fully hereinafter described operates. The handle member I2 is provided with a pistol grip l terminating at its upper end in a head oscillated about the pivot 28.

I iprovided with an internally screw threaded socket i llffor engagement with the threads of the frame l0, and this socket opens at its inner end into a chamber 18 in which the saw driving mechanism is mounted. Opening through. one side of .theiframef I2 is an internally screw threaded opening is which communicates with the chamber l8 and is adapted to receive an externally screw. threaded nipple 20 in which is rotatably mounted a. barrel 2! carrying at one end afcrarlle disc 22 which rotates in a plane with [one sidepof the chamber Ill. The opposite end of the barrelis held in placein the sleeve 20 by ma sion stop collar23, and is provided with an axial boss 24 terminating in a squared portion 25 for. connection with a conventional coupling to whichthe drive element of a flexible shaft 26 is connected. Theopposite end of the flexfible. shaftf26 is connected with a prime mover 20 (not shown) such as an electric motor, so that WhentheIprime mover issetinto operation the barrel 2! and crank disc 22 will be rotated within the nipple 20. A crank pin 21 projects from one face of thecrank disc 22 and operates in the charhber l8 in janj orbitalpath as will bereadily understoodupon reference to Figure 2.

HPivotally mounted in the frame [0 substan- 1tiallymidwaybetween opposite ends as at 28 isjtheshank 2 9 of a saw designated generally M30130, one end of this shank extends into the chambrlB and isprovided with an elongated slot 3| "in which trietranapm 2"!"is received, so that when the disc 22 is rotated the saw will be The end of the shank 29 of the saw 30 opposite that containing the slot 3! is provided with a head 32 carrying across its end a row ofsaw teeth 33.

Telescopically associated with the frame l0, and slidably mounted over the end opposite that carrying the handle I2 is a sleeve 34 carrying at the end opposite the one which telescopes on the frame Ill a saw guard designated generally 35. This saw guard comprises a pair of longitudinally spaced heads 36 each provided with spaced longitudinally extending arms 31 the inner edges of which are generally arcuate configuration, and serrated as at 38 effectively to grip the object being operated upon. The ends of the arms 31 are joined by pins 38' which serves to hold the arms in spaced parallel relation at their outer ends in order to provide a clearance space 39 in which the head 32 of the saw 30 moves.

The sleeve 34 is provided with a longitudinally extending slot 40, and entering the frame l0 radially near its forward end is a stop pin 4| which serves to limit the longitudinal sliding movement of the sleeve 34 on the frame III. A compression coil spring 42 surrounds the shank 29 of the saw 30 between the inner ends of the frame In and the head 35 so as yieldingly to urge the head away from the frame and retract the saw beyond the innermost confines of the work gap 43 formed between opposite pairs of arms 31.

In the modified form of the invention illustrated in Figure 7, a saw guard designated generally 44 comprises a pair of longitudinally spaced heads 45 each of which is provided with a sub? stantially semi-circular boss 46 for entrance into the end of the sleeve 34 opposite that which receives the tubular body ll.

These bosses are! detachably secured in the tubular body by dia-' arms being adapted partially to embrace and steady an object'to be operated upon, said saw metricallyopposed screws 41 so that the'heads may be held in spaced parallel relation to form a slot in which the toothed edge of the saw works. Formed along the ends of the heads 45 opposite those carrying the bosses 4,6 are serrations 48 for contact with a bone to be operated upon. i

In use, it will be understood that theinstrument is placed over the bone to be severed with the bone entering the work gap 43 and the serrations 38 bearing on the bone. The saw is then set into operation by drivingthe disc 22 and upon grasping the pistol grip l5 and exerting pressure against the bone, the spring 42 will be compressed to cause the teeth 23 of the saw head 32 to engage the bone. In this manner, the depth of out may easily be regulated through the release and application of pressure against the pistol grip l5, and where conditions require, the bone may be sawed in two in a plane perpendicular to its longitudinal axis. It is to be noted that the head 35 engages the bone on both sides of the saw blade so that the pressure on both sides of the out being made is equal at all times and consequently any splintering will be avoided. Obviously, the saw guard 44 may be substituted for the saw guard 35 and with this type of saw guard longitudinal or diagonal cuts may be made should occasion require, it being understood that the depth of cut may be regulated according to the pressure on the pistol grip.

While in the foregoing there has been shown and described the preferred embodiment of this invention it is to be understood that minor changes in the details of construction, combina- 7 Number guard having a longitudinal saw receiving slot which extends through the arms, means within the saw guard yieldingly to hold the saw retracted into the slot, and means to oscillate the saw about its pivot.

21 A surgical instrument comprising an elongated frame, a pistol grip at one end of the frame, a saw pivoted in the frame to swing in a plane lying alongthe longitudinal a is o the frame. a saw guardteles'copically enclosing the frame at the end opposite the pistol grip, spaced arms extending longitudinally from the saw uard, said arms being adapted partially to embrace and steady an object to be operated upon, said saw guard having a longitudinal saw receiving slot which extends through the arms, means within the saw guard yieldingly to hold the saw retracted into the slot, a crank disc mounted in the frame to rotate about an axis lying perpendicular to the longitudinal axis of the frame, anda crank pin carried by the crank disc and engaging the saw to cause the saw to oscillate when the crank disc is rotated.

GAY V, CARROLL.

REFERENCES CITED following references are of record in the file of this patent:

UNITED STATES PATENTS v Name Date 1 K ester in. Dec. 15, 1908 Meyer Aug. 16, 1910 Allen "-4, Oct- 29, 1935 FOREIGN PATENTS Country Date Germany June 24, 1929 Number 

